Public Bath No.3 Wata-no-yu

Day Use

Yes

06:00–22:00

if you have the key when staying at the ryokan

¥0

when staying at the ryokan and with a key

Bathing & Water

Natural onsen water

Uses natural hot spring water

Outdoor BathNo

Open-air outdoor bath

Indoor BathYes

Enclosed indoor bathing area

SaunaNo

Sauna room of any kind

Cold BathNo

Cold water plunge bath, typically used after sauna

Bathing Arrangements

Private BathNo

A private bath you can reserve for yourself or your group

Mixed BathingNo

Shared bathing area for all genders

Policies & Services

WashingNo

Shower, wash stations, soap and shampoo provided

渋温泉総合源泉

Shibu Onsen Combined Source

Mixed source

硫

Sulfate

+ Chloride

Color: faintly yellow and clear
Taste: a faint iron taste
Odor: odorless

Sodium-Calcium Sulfate-Chloride spring

pH 4.6Weakly acidicHot source · 65°CHigh silica

Composition fingerprint1.2 g/kg dissolved · Hypotonic

Na⁺55

Ca²⁺34

SO₄²⁻53

Cl⁻45

◀ CationsAnions ▶

Sodium Na⁺: salt's cation — pairs with chloride to make the water salty.
Sulfate SO₄²⁻: "gypsum / Glauber's salt" — vessels and wound healing.

Known good for

Aches & jointsstiff shoulders
Circulationtired legs
Warmingcold sensitivity

Shibu Onsen's combined source blends three wells — Hira-no-yu, Yakushi-no-yu and Bitonbi-no-yu — and is drawn on the grounds of Onsenji temple. It is a sodium-calcium sulfate-chloride water: sulfate gives it a settled, mineral body with a salty edge layered on top. At 65.0 °C it sits among Japan's hottest natural sources, yet the weakly acidic pH keeps the touch gentle rather than sharp. The water runs faintly yellow and clear at the spout, odorless, with a faint iron taste on the tongue. Metasilicic acid at 151.4 mg/kg puts it in Japan's beauty-water family, leaving the kind of thin silica film that makes skin feel noticeably smoother.

Sampled at wellhead·Analyzed Jun 10, 2016·一般社団法人上田薬剤師会検査センター·Cert no. 中28-5(No.430)

Explore the water